Re: [PATCH 2/3] KVM: x86: Save&restore interrupt shadow mask

Gleb Natapov
2010-02-17T09:10:11Z

On Wed, Feb 17, 2010 at 10:03:58AM +0100, Jan Kiszka wrote:
> >
> > Also, as Avi mentioned it would be better to avoid this. Is it not
> > possible to disallow migration while interrupt shadow is present?
>
> Which means disallowing user space exists while the shadow it set? Or
> should we introduce some flag for user space that tells it "do not
> migration now, resume the guest till next exit"?
>
I think disabling migration is a slippery slope. Guest may abuse it. May
be it will be hard to do with interrupt shadow, but the mechanism will be
used for other cases too. I remember there was an argument that we
should not migrate while vcpu is in a nested guest mode.

--
Gleb.